Excavating apparatus



April 27, 1 948.

C. A. ERICKSON EXCAVATING APPARATUS Filed July 27, 194's 4 Sheets-Sheet1 Cam. HHEEICK5ON) April 27, 1948 c, ERICKSON 2,440,501 v I EXCAVATINGAPPARATUS Filed July 27, 1945 4 Sheets-Sheet 2 mm. H. filcxsom A ril 27,1948. c, A. RICKSON 2,440,501

EXCAVATING APPARATUS Filed July 27, 1945 4 Sheets-Sheet 3 CARL. Pl.EEICKSON) .mrhm

April 27, 1948. c, A, ERICKSON 2,440,501

EXCAVAT ING APPARATUS 'Filed July 27, 1945 4 Shets-Sheet 4 CARI. H.fi'lcxsow,

Patented Apr. 27, 1948 STATES PAT 12 fila ims.

The invention 'i'elate's to improvements: in excava'ting apparatus.

An object of the present invention is to provide an excavating apparatuscapable of rapid and economical excavation in shaft sinking "operationsin "bIastinganci in the i'emov'al of the blasted material at the bottomof shafts.

A runner object ofthe invention isto provide an excavating apparatuscapable of enabling shafts to be su'n'k 'in' fnining'and otheroperations in nrnchless tiirie and with much less labor than is possiblethe manual handling or shoveling of the blasted inaterial, whereloy "the'cost of 'snch xoavatiofis he Q'laitlir red'u'ced and the speed vastlyincreased. 1

A further object of the invention is to provide an excavating aptarsrusedni'pped with conveniently located drillsfor boring holes to receiveblasting charges and a hinged boom carrying a pivoted excavating dipperor scoop and mounted for movement transversely of the hole or shaft andcapable of enabling theexcavating dipper or scoop to rempve the blastedinaterial from the entire area or the Bottom of the shaft or hole anddeposit the "excavatedinatriai into elevat in'g Skips for "hoi'sti'iigthe 'fdcavaltd'materi'al t the top of theshaftor hole.

Another object or the invention is 120 provide an excavating emanates orthis character adapted to he progressively-lowered to excavate the shaftor hole to the iqifiiddepth and provided with 'aidjiis fiabl e means forfeiiablir'ig it, by positively engaging on osite Walls of the shaft orhole, "to he 'secnrei y anchored'in each successive lowering operation.

Another object of the ih'ventidnfis to provide an 'eXCavatifig apparatus"dt'i'nipli'sir'ig a niain frame and a carriage 'sli'clflo'li'e "thereonforwardly and rearwardly and earning s'aid trans'verselir slidahlebeam-winner the b'o' 'vvith its excavating dipper or scenes lie a;c :'nrate1y iios'iti'oned and crones siven adusted for complete removal ofthe blasted rial.

A {hither tbje't t; the invention is 'to enable the carriage to beadjusted and thehin'g'e'd tom and ext'en e section and the pivoteddipper or scoop to he attested and controlled hi cable's teased bymechanism {arranged on the carnage convenient position for operation byan attenda-nt.

reg mm the eerie or neither-1s any of the advantages or the inveinian.

In the drawings: Fig. '1 is aside elevation, partly section,

of an excavating apparatus constructed in accordance. with thisinventionand shown arranged in a shaft or hole.

Fig. 2 is a plan view 10f the same, partly'in section. i V

Fig. 3 is anenlargfeddetai-l sectional view illustrating theconstruction 'of the hinged boom and the pivoted dipper or scoopandillustrating the arrangement "of the cables {for controlling thehinged and pivotal movements of the boom and dipper or scoop and foradjusting the 'ex'tensiiole telescopic section of, the. boom. I

Fig. l isa-n-enlarged detail elevation illustrating the arrangement ofthe *guide's'for the skips.

Fig. '5 is anenlarged detail sectionalview'showme one :of the skins and'the 'means for guiding the same.

Fig. 6. is a detail view of a portion of one 'of the sectional skipguides. v

Fig. '7 is an enlarged detail {sectional View of a portion of. thecarriage and illustrating the arrangement of the upper :and lower guidesfor slidably mounting the carriage "on the Ina-"in frame.

Fig. 8 is a detail sectional view-illustrating the manner of mountingthe slidabie bracket and sheave of the boom hoisting cable.

Fig. 9 is an enlarged detail sectional view *i-ll'n'strating the mannerof slidably mounting the longitudinal bars :of the extensible section ofthe main frame and :also the slidable connection of the longitudinalbars with the transverse connecting bars.

Fig. '10 is an enlarged detailsectional View takensubstantially on theline 10-40 of Fig. 3 and illustrating the construction of the boom, theextensible section, and the manner of mounting' the upper and lower"sheaves thereof.

Referring to the. drawings, in which is illustrated the preferredembodiment of the invention, the excavating apparatus comprises in itsconstruction an open main frame 1 composed of vertical bars -2-and top'and "bottom longitudinal and transverse connecting liars 3 and '4 andpro"- vided at the bottom with a depending ffarnework 5 :on which aremoimt'ed a; plurality "ii-{phenmatic drills .6 arranged in convenientposition for ready removal and use for drilling holest'o receiveexplosive charges for blasting mater al at the bottomfof a shaft 'orhole 1. The phenmatic drills are designed to be of the erdm ry don"-struction customarily "employed for "drilling li'oles for explosivecharges arid 'as any 'eanstrucndn of pneumat c er ether type oriidrtatieenii may be employed; illustration 151E the particular drill ofthis character is deemed nnnecessary.

The main name, which -is oBfifiotd-with-l'ioisting cables 8 to'euanieitto be progressively lowered in excavating a shaft or hole andto be removed therefrom, is substantially rectangular in plan andelevation and is provided at one end with fixedwall engaging anchoringprojections 9 and at the other end with'an adjustable section l9 havingwall engaging anchoring projections H. The anchoring projections 9 andII are arranged in pairs at the top and bottom of the main frame and theadjustable section thereof and penetrate the opposite walls of the shaftor hole and securely anchor the main frame in each adjustment thereof.While two pairs of anchoring projections are shown in each end of themain frame, any number of such projections may of course be employed.-.

The adjustable section of the main frame is composed of verticalbars l2,transverse connecting bars 13, and-top and bottom longitudinal bars M towhich are connected hydraulic jacks l5 arranged in pairs at the top andbottom of the'main frame and adapted to thrust the anchoring projections9 and II firmly into engagement withthe opposite wallsof the shaft orhole [for anchoring the main frame.

The hydraulic jack may 'be supplied with fluid pressure by 'any suitablemeans for forcing the plunger portion '16 of the jack outwardly. Theadjustable section. lfl 'of the main frame is slidable thereon audit isretracted to withdraw the anchoring projectidns" H from the engaged wallof the hole orishaft by means of spaced cables ll. connected at theirouter ends with the slidable sectionv of the main fr'ame'and havingtheir inner portions connected to and arranged to be wound on drums l8having cranks l9 or other suitable means for rotating the same forwinding the .cables l'l'on the drums. When the anchoring projections I Iare withdrawn from the engaged'walLLthe anchoring projections 9 may bereadily disengaged from the opposite wall and the cables I! and drums I8will hold the slidable section of 'the'main frame in its retractedposition while lowering the excavating apparatus from one position toanother.

i The main frame is provided at the top and bottom with upper and 'lowerhorizontal guides Zila'ndrZl arranged in pairs and located at oppositesides of the main frame and provided with grooves 22 and 23 for thereception of upper and lower rollers 24 and 25 of a carriage 26 slidablelongitudinally of the main frame. The carriage consists of a frameworksubstantially rectangular in plan and elevation and having a platform 21and provided (at the rear end with a transverse channel guide 28 whichslidably receives a slide portion 29 of a bracket or hanger 38. Thechannel guide is provided at its open side with inwardly extendingflanges 3| forming upper and lower grooves which receive upper and lowervertical flanges 32 of the slide portion 29 of the hanger or bracket 39,whereby the hanger or bracket is slidably interlocked with thehorizontal'guide and is adapted to, slide in the guideythereof. Anysuitable anti-friction means may of course. be provided for reducing toa minimum friction incident to the hanger or' bracket traversingthe'guide 28. The hanger or bracket carries a depending'pivoted orhinged boom 33 depending from the hanger or bracket and from thecarriage and connected to the hanger 'or bracket byv a pivotalconnection which maybe in the formiof a-knuckle joint as shown andhaving a pivot 34.

. The'boom, which is constructed of suitable metal; is tubular andtelescopically receives an extension section 35 which is adjustable bythe means hereinafter described to vary the effective length of theboom. The boom, which is adapted to swing forwardly and rearwardly, isprovided at the lower or outer end of the extension section with adipper or scoop 36 which is .connected with said extension section 35'by a pin or pivot 31. The dipper or scoop is adapted to swing downwardlythrough gravity to an inclined, position as illustrated in Fig. 1 of thedrawings for engaging loose material at the bottom of the shaft and theboom is adapted to be swung forwardly and upwardly for carrying thedipper or scoop into engagement with the material and for elevating thedipper or scoop to a point above one or the other of a pair of elevatorskips 38 which conveys the excavated material to the top of the shaft.The boom is adapted to swing downwardly and'rearwardly by gravity froman elevated position to the depending vertical position illustrated inFig. 1 of the drawings.

The dipper or scoop, which is provided at the bottom with a projectinglip 39 and which is gravity acting in one direction, is controlled by acable 40 extending upwardly from the topof the dipper or scoop andsecured at its lower end to an ear 4| of the scoop. The cable 49 extendsupwardly along the boom 33 and is guided by upper and lower sheaves 42and 43 mounted in suitable bearings 44 and 45 which may be formedintegral with the tubular metal boom but the sheaves may be mounted inany other desired manner. I

'I'he'cable 40 extends from the upper sheave 42 to a sheave 46 of thehanger or bracket39 and then upwardly toan overhead pulley or sheave 4'!and then to a drum 48. The drum 48, which is mounted in suitablebearings on the platform 21, is disposed transversely thereof and it maybe operated by an electric motor 49 or any other suitable means. Thecable 451s wound around the drum for swinging the dipper or scoopupwardly for arranging it in proper position for scooping or dipping upthe loose material at the bottom of the shaft and' when it is carriedinto an elevated position above one of the skips 38 it-is released byslackening the control cable 40, thereby permitting the scoop or dipperto swing downwardly and discharge its contents into said skip.

The boom is controlled by a hoisting cable 50 secured at its lower endtoan ear 5!, preferably formed integral with the extensible section of theboom and located near the lower or outer end thereof. The cable 59extends upwardly and forwardly from the lower or outer portion of theboom to a sheave or pulley 52 mounted in a bearing bracket 53 having aslide portion 54 slidably mounted in a guide 55 disposed transversely ofthe front end of the carriage-at a point adjacent the platform 21. Theslidable bearing bracket 53 which may, if desired, be provided with anysuitable anti-friction. devices, is arranged in alignment with thehanger" or bracket 39 and is adapted to slide transversely of thecarriage simultaneously with the hanger 30 when the boom is shiftedlaterally in either direction. The cable 50 extends rearwardly betweenspaced centrally arranged guide pulleys or sheaves 56 located at thefront end of the platform of the carriage and it extends from thecentrally arranged pulleys 56 to, and passes between, a pair of spacedguide pulleys or sheaves 51 located in advance of a transverselydisposed drum 58 located in transverse alignmentywithvthe drum 4T8 onwhich the-dipper orscoop -controlling-.cable is wound. The drum 58 is:actuated by :anelectric motor -59 or other suitablemeansandthe-cable-Eil ,is wound around the 'drum 58 .for swinging the boomlupwardly andwhen the cable 150 --is slackened, the boom will swingdownwardly through :gravity.

The (hanger or bracket 130 and the bearing bracketifi are simultaneouslymoved-in the same direction transversely of the carriage by means ofcables -60, -6 l, -62, and .63 (arranged in, pairs as clearlyillustrated in Fig. 2 of the drawings. The cables :60 landfillare-secured at one end to the hanger or bracket at DP osite sidesthereof and they rextendilaterally from the :hanger or bracket topulleys 'or sheaves 64 and -65 located at ppposite sides of the=carriage-Fhe 'said cables iii! and :61 then extend around the pulleys or-sheaves64 :and -65 and then inwardly to spaced pulleys or sheaves B6 and :61,and" then forwardly to :a transversely =disposed drum 68 on which :thecables are reversely wound.

The other pair of cables =62 and 63 are secured to the hanger -orbracket 30 at opposite sides thereof adjacent the points of attachmentof the said :cables 60 and-t8! and they extend laterally from the hangeror bracket "36 to pulleys or sheaves 6B and'HJlocated'at-oppositersidesof the carriage. They then extend forwardlylongitudinally-of the carriage to spaced pulleys H andiZ located atopposite sides -of the carriage at the front portion thereof. The cables-52 and, 63 then extend transversely of the carriage, crossing eachother centrally thereof and passing around side pulleys or sheaves t3and at and then to the bearing bracket 55 "to which they are connected.The transverse'drum 68 is controlled by means of an electric motor 15and when rotated in one direction, the hanger or bracket =35 and thebearing bracket 55 are simultaneously moved in the same direction, andsvhen th'e drum is rotated in the opposite -di-rection,*the direction ofmovement of the hangeror bracket -33 and the bearing bracket 55 isreversed.

The telescoping :sectionSE-of the boom ismoved inwardly or upwardly bymeans of a line or-cable 16 secured at one end to an car on the inner orupper end of the boom. This l-inefit extends downwardly or; outwardlyalong the interior of the telescoping section to and arounda pulley orsheave 18 mounted on theyouter or lower portion of the telescopingsection and it then extends upwardly .or inwardly through thetelescoping section and the boom to an overhead pulley or sheave 19mounted on the vmain frame. A line or cable 80 is secured to the upperend of (the telescoping section at .81 and extends downwardly oroutwardly to and around the lower pulley 82 and then upwardly throughthe telescoping section and the boom to an overhead pulley or sheave 83.The cables or lines 16 land 85) extend from the overhead pulleys 19 andfiflto a drumtd and are reversely wound around the same so that when thedrum is rotated, one of the lines or cables will be wound on the drumand the other unwound therefrom. I

The telescoping section 35 with the pivoted dipper has sufficient weightto move downwardly or outwardly by gravity :action and this arrange mentof the lines or cables 1'6 and 80 affordsibet ter control oi? thetelescoping section than a single line or cable. The drum is mounted onthe platform 2'! and is actuated by an electric motor 85 or othersuitable means.

The carriage is moved .for-wardly and rear- .6 I wardly along thermainframe 'by meansof babies or lines 86 and v81 extending longitudinally ofthe main frame from an intermediate point on the carriage to the :frontand rear ends of the mainframe. The cable or line 86 i-s-secured atitsouteror-front end at=88 tothe extensible section-oi i-the'mainirameand the other-cable or line 81 is -:secured at its outer or rear end at89 to the rear end of. theimain 'frame. The inner portions of the eablesB6 and 8-1 are reversely wound around a drum 90 so that when the-drum isrotated'on'e of the .cables will be wound :around thedrumeil and theother'cable unwound therefrom and the carriage moved longitudinally ofthemainirame. The drum 90 which is mounted on the platform? of the.carriageis actuated by anielectricmotor 9| :or other suitable means.

Theskips 38, which are alternately raised and lowered by hoisting cables82 to'convey the excavated material to the surface of the .ground and to--return the empty skips to the bottom-of the hole, are provided at theback and sides with short vertical slides es and -94 having outerflanged webs providing :portions substantially T- shaped in crosssection to slide in and interlock with rear and side channel guides 55and 96. El he rear and side channel guides have spaced transverseflanges 9i and 98 forming slots: which receive the web portionsof theslides 93 and 94 of the skips '38. :Any other suitable form ofslides-and-guides may be providedfor guiding the skips '38 in theirvertical movement.

rA-s the hole deepens, it is designed to be timbered as shown at 99 butthe walls may be coated or walled with cement or any other suitablematerial to provide a liningtor the hole and prevent caving in-of thewalls thereof. The guides for the skips are designed to be constructedof sections and to be extended as the hole. deepens. The adiacent endsof the sections of the guides may be connected by suitable joint such asare illustrated at liiflrin Fig-60f the drawings. The sections of theguides are designed to be supported by the timbered portion of the holeand also by the framework of the main frame and when :moving theapparatus from a hole, sections of :the guides may be pinned to adjacenttimbers as illustrated at till in Fig-6 of the drawings.

The boom -33 ls rectangular in-crosssection and the extensiblesection,which may be constructed in any desired manner, is preferably composedof spaced parallel side bars or members I02 and H33 which are connectedtogether at their upper andlower terminals and which slidably fit theinterior oi the boom. The upper pulley 18, around which the cable 15passes, is mounted on the side bar "or member I02 within a-bear-ingbracket it! and when the cable 16 is wound around its the telescoping"section will be moved upwardly or inwardly.

The lower pulley 52, around which the cable 86 passes, is carried by theboom and is located adil icentthe other side bar or member l03of thetelescoping section. The boom is provided with hearing brackets L235 inwhich the lower pulley 824s mounted. The bearing brackets are secured tothe boom at opposite sides thereof and when the cable 813 is Woundaround its drum, the telescoping section will be positively moveddownwardly and outwardly.

In order to enable the longitudinal bars of the extensible section ofthe main frame to be adjusted independently of each other to positionthem properly to engage the irregular surface of a hole, thelongitudinal bars M are slidably -con nected with the transverse bars l3and are provided'with guides or ways I06 in Which slide approximatelyT-shaped terminal portions I01 of the transverse bars, whereby thetransverse bars and thelongitudinal bars are slidably interlocked witheach other. Any suitable means, such as a clamping'screw I08, may beprovided for rigidly securing the longitudinal bars in any adjustedposition to suit the character of the surface to be engaged by theprojections ll.

What is claimed is:

1. An excavating machine including a main frame provided at oppositesides with longitudinal ways'and having means for engaging walls of anexcavated hole for securing the main frame in different positions insaid hole, hoisting means connected with the main frame for lowering itinto said hole as the excavation of the same progresses and for removingit from the hole when the excavation thereof is completed, a carriageslidable in the ways of the main frame and provided with a transverseguide, a pivoted boom mounted for sliding movement backand forth alongsaid transverse guide and provided with an extensible section, a dipperpivotally mounted on the extensible section of the boom at the outer endthereof, means for actuating and controlling the boom to swing the sameand to slide the boom along said transverse guide, means for effectingadjustment of said extensible section to vary the effective length ofthe boom, and a dipper line connected with the dipper and guided on andcarried by the boom in the sliding movement thereof. 7

2. An excavating machine including a main frame provided at one end withfixed projections for engaging a wall of an excavated hole and having atthe other end an extensible section slidably mounted on the main frameand provided with projecting means for engaging the opposite wall ofsaid hole, hydraulic jacks mounted on the main frame and connected withthe extensible section for moving the sameoutwardly to engage saidprojections with said walls of the hole for adjustably securing the mainframe in position for excavating, excavating means carried by anddepending from the main frame for excavating the hole below the mainframe, drums having lines wound thereon and connected with theextensible section, and means for rotating the drums for moving theextensible section in- Wardly.

3. An excavating machine including a main frame provided at oppositesides with longitudinal ways and having means for engaging walls of anexcavated hole for adjustably securing the main frame in said hole, acarriage slidably mounted in the ways of the main frame and providedwith front and rear transverse guides, front and rear brackets slidablein said guides, a boom pivoted to the rear bracket and dependingtherefrom, a dipper carried by the boom, a cable connected with the boomand guided on the front bracket for swinging the boom, and means mountedon the carriage and connected with the front and rear brackets forsimultaneously sliding the same in the same direction along thetransverse guides.

4. An excavating machine including a main frame provided at oppositesides with longitudinal ways and having means for engaging walls of anexcavated hole for adjustably securing the main frame in said hole, acarriage slidably mounted in the ways of the main frame and providedwith front and rear transverse guides, front and rear brackets slidablein said guides, a boom pivoted to the rear bracket and dependingtherefrom, a pivoted dipper carried by the boom, a cable connected withthe boom and guidedonthe front bracket for swinging the boom, meansmounted on the carriage and connected with the front and rear bracketsfor simultaneously sliding the same in the same direction along thetransverse guides, and a dipper line connected to and controlling thepivoted dipper and extending along and guided by the boom and the rearbracket.

5. An excavating machine including a main frame, means for adjustablypositioning the main frame in an excavated hole, excavating mechanismcarried by the main frame and including a pivoted boom having a pivoteddipper, operating means connected with the boom and the dipper forswinging the boom and for permitting the dipper to discharge itscontents, skips movable vertically through the main frame for conveyingexcavated material to the surface of the'ground and adapted to receiveexcavated material from the dipper when at the lower limit of theirvertical movement, said skips being provided with vertical slides andextensible vertical sectional guides receiving the slides and extendingfrom the top to the bottom of the hole, sections of the guides beingmounted on the main frame, and hoisting cable connected with the skipsfor raising and lowering the same.

6. An excavating machine including a main frame, means for adjustablypositioning the main frame in an excavated hole, excavating mechanismcarried by the main frame and including a pivoted boom having a pivoteddipper, operating means connected with the boom and the dipper forswinging the boom and for permitting the dipper to discharge itscontents, skips movable vertically through the main frame for conveyingexcavated material to the surface of the ground, said skips beingprovided at the sides and rear with vertical slides, extensive verticalsectional guides receiving said slides'and extending from the top to thebottom of the hole, and hoisting cables connected with the skips forraising and lowering the same.

7. An excavating machine including a main frame provided withlongitudinal ways, a carriage slidably mounted in said ways and providedwith front and rear transverse guides, front and rear brackets slidablein a transverse guide, a boom pivoted to and depending from the rearbracket, a dipper carried by said boom, a cable connected with the boomfor swinging the boom upwardly, said cable extending to and guided onthe front bracket and movable with the same when the front bracketslides along the front guide, a drum mounted on the carriage, cablesreversely wound aroundthe drum and connected with the rear bracket andextending laterally in opposite directions therefrom, means for guidingsaid cables to said drum, front cables connected with and extendinglaterally from the front bracket and crossed intermediate of their endsand extending to opposite sides of the rear portion of the carriage andlaterally therefrom to the rear bracket and connected therewith, andmeans for guiding the cables which are connected with the front bracket,said drums when rotated being adapted to move the front and rearbrackets simultaneously in the same direction.

8. An excavating machine including a main frame provided withlongitudinal ways, a carriage slidably mounted in said ways and providedwith front and rear transverse guides, front and rear brackets slidablein a transverse guide, a boom pivoted to and depending from the rearbracket, a dipper carried by said boom, a cable connected with the boomfor swinging the boom upwardly, said cable extending to and guided onthe front bracket and movable with the same when the front bracketslides along the front guide, a drum mounted on the carriage, cablesreversely wound around the drum and connected with the rear bracket andextending laterally in opposite directions therefrom, means for guidingsaid cables to said drum, front cables connected with and extendinglaterally from the front bracket and crossed intermediate of their endsand extending to opposite sides of the rear portion of the carriage andlaterally therefrom to the rear bracket and connected therewith, meansfor guiding the cables which are connected with the front bracket, saiddrum when rotated being adapted to move the front and rear bracketssimultaneously in the same direction, hoisting cables connected with themain frame, and means for adjustably positioning the main frame in anexcavated hole.

An excavating machine including a main frame of approximately the sizeof the hole to be excavated provided at opposite sides with ways andhaving means for engaging walls of an excavated hole for securing themain frame in different positions in said hole, hoisting means connectedwith the main frame for lowering it into the hole as the excavation ofthe same progresses and for removing the main frame from the hole whenthe excavation thereof is completed, a carriage slidable in the ways ofthe main frame and extending across the same and provided with twoseparate spaced guiding means extending transversely of the carriage, apivoted boom mounted for movement along one of said transverse guidingmeans, a dipper carried by said boom and means mounted for slidingmovement in the other of said guiding means and connected with the boomcontrolling the pivotal movement thereof.

10. An excavating machine including a main frame of approximately thesize of the hole to be excavated provided at opposite sides with waysand having mean-s for engaging walls of an excavated hole for securingthe main frame in different positions in said hole, hoisting meansconnected with the main frame for lowering it into the hole as theexcavation of the same progresses and for removing the main frame fromthe hole when the excavation thereof is completed, a carriage slidablein the ways of the main frame and extending across the same and providedwith two separate spaced guiding means extending transversely of thecarriage, a pivoted boom mounted for movement along one of saidtransverse guiding means, a dipper pivotally mounted in the boom at theouter end thereof, means mounted for sliding movement in the other ofsaid transverse guiding means and connected with the boom forcontrolling the pivotal movement thereof, and separate means connectedwith the dipper and extending along the boom and carried with the samein the sliding movement thereof.

11. An excavating machine including a main frame of approximately thesize of the hole to be excavated provided at opposite sides with waysand having means for engaging walls of an excavated hole for securingthe main frame in different positions in said hole, hoisting meansconnected with the main frame for lowering it into the hole as theexcavation of the same progresses and for removing the main frame-fromthe hole when the excavation thereof is completed, a carriage slidablein the ways of the main frame and extending across the same and providedwith front and rear guiding means extending transversely of thecarriage, a pivoted boom mounted for sliding movement in the rearguiding means and provided with an extensible section, a dipper carriedby the extensible section of the boom, means mounted in the frontguiding means for sliding movement transversely of the carriage andconnected with the boom for controlling the pivotal movement thereof,and means connected with the extensible section of the boom andextending along the boom and carried by the same in its sliding movementand connected with the extensible section for effecting adjustment ofthe extensible section to vary the effective length of the boom.

12. An excavating machine including a main frame of approximately thesize of the hole to be frame and 'slidably mounted in the ways thereofand provided with front and rear transverse guiding means, a bracketslidably mounted in the rear guiding means for movement back and forthin said guiding means, a boom pivoted to and depending from the bracket,a dipper pivoted to the outer end of the boom, means mounted in thefront guiding means for sliding'movement transversely of the carriageand connected with the boom for controlling the pivotal movement thereofand separate means connected with the dipper and extending along theboom andcarried by the same in the sliding movement thereof forcontrolling the pivotal movement of the dipper.

CARL A. ERICKSON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 265,592 Fox Oct. 101, 1882564,727 Trainor July 28 1896 820,055 Libbe May 8, 1906 1,048,244 WardDec. 24, 1912 1,171,686 Zaitz Feb. 15, 1916 2,326,172 Riddell Aug. 10,1943 2,358,543 Tofilemire Sept. 19, 1944 FOREIGN PATENTS Number CountryDate 486,168 Germany 1929 1,682 Great Britain 1868 11,219 Great Britain1896

